IR safety glasses are glasses that are designed to protect the eyes from infrared radiation. Infrared radiation is a type of electromagnetic radiation that has a longer wavelength than visible light and is not visible to the human eye. IR radiation can cause damage to the eyes and can lead to conditions such as cataracts and retinal burns. IR safety glasses are typically made from materials that are able to block or absorb IR radiation, such as special coatings or filters. They are commonly used in industrial settings and in situations where individuals are exposed to high levels of IR radiation, such as welding or working with lasers. IR3 protection is designed to block or absorb radiation in the range of 780-1300 nm, which is considered the "near infrared" range. This type of protection is typically used in situations where the primary source of infrared radiation is incandescent or halogen lights. IR3 glasses are also used in some welding applications, where they provide protection against the infrared radiation emitted by the arc. IR5 protection, on the other hand, is designed to block or absorb radiation in the range of 2000-3000 nm, which is considered the "far infrared" range. This type of protection is typically used in situations where the primary source of infrared radiation is a laser, as well as in some industrial applications where high intensity infrared radiation is present. IR5 glasses are typically considered to provide a higher level of protection than IR3 glasses. It is important to note that IR safety glasses are often rated based on their ability to block or absorb radiation at specific wavelengths, and that the specific type of protection (IR3 or IR5) may vary depending on the manufacturer or standard being used.